Ocean Acidification: Influence of Ocean Acidification on Biotic Controls of DMS Emissions

海洋酸化：海洋酸化对 DMS 排放生物控制的影响

• 批准号: 1316133
• 负责人: Stephen Archer
• 金额: $ 129.05万
• 依托单位: Bigelow Laboratory for Ocean Sciences
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-10-01 至 2018-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1316133&HistoricalAwards=false
• 关键词: Ocean; Acidification; Influence; Biotic; Controls

To date, investigations into the biogeochemical consequences of predicted increases in pCO2 and reduced pH in the oceans (ocean acidification, OA) over the next century have largely focused on the production and fate of carbon. Considerably less is known about how OA will influence other biogeochemical cycles or the exchange of reactive trace gases between ocean and atmosphere. Variations in trace gas exchange will alter atmospheric chemistry, including aerosol formation and growth, and potentially feedback on climate change. In this project, a research team at the Bigelow Laboratory for Ocean Sciences will study the influence of OA on the biological processes that govern the concentrations and hence emission, of dimethyl sulfide (DMS) in the surface oceans. The team will study OA effects on the DMS-cycle in three natural-water mesocosm experiments designed to encompass natural community responses to predicted changes in pCO2 of varying degrees. They will exploit the opportunity to participate in a major experiment in sub-tropical oceanic waters involving the deployment of nine large scale (~60 m3) free floating, pelagic mesocosms, as part of the German-funded BIOACID Program. Two replicate experiments conducted using the new mesocosm facilities at Bigelow will further expand the environmental range of DMS-OA studies. Through a combination of standard analytical approaches, recently developed cutting-edge tracer approaches to determine process rates, as well as the underlying organism diversity and genetic response of microbes involved with biogenic sulfur cycling, they will determine how altered pH influences key biological pathways governing DMS concentrations and the organisms responsible during the experiments. Broader Impacts: The information generated will be used to inform on-going development of global ocean-atmosphere coupled models, able to examine the influence of ocean acidification on climate change. The information will also be used to further develop physiology-based mechanistic approaches to biogeochemical ecosystem models. A Postdoctoral Research Scientist will be trained in the experimental approaches, will gain modeling experience by working with European scientists, and will develop international and US collaborations, with a common aim to increase our understanding of ocean acidification on ecosystem function. Four undergraduates, two interns and two REU-students, will gain valuable experience by participating in the Bigelow experiments. An additional undergraduate with a mathematical background will be mentored in and participate in the interpretation and modeling aspects. Extensive outreach to K-12 students and teachers as well as the general public will be pursued as part of established Bigelow programs in which all PIs will participate (BLOOM, Cafe Scientifique). Joint programs with Colby College (Changing Oceans semester) and Island Institute will reach undergraduates and Maine island K-8 schools, respectively.

迄今为止，对PCO2预测增加的生物地球化学后果的调查和海洋pH值降低（OACHIFICATION，OA）在下一世纪，主要集中在碳的生产和命运上。关于OA将如何影响其他生物地球化学周期或海洋和大气之间反应性痕量气体的交换知之甚少。痕量气体交换的变化将改变大气化学，包括气溶胶的形成和生长，并有可能对气候变化的反馈。在该项目中，Bigelow海洋科学实验室的一个研究团队将研究OA对浓度且因此排放的生物学过程的影响，该过程是地表海洋中二甲基硫化物（DMS）的影响。 该团队将研究OA对DMS周期的影响在三个天然水中辅助实验中，旨在涵盖自然社区对不同程度上PCO2的预测变化的反应。他们将利用机会参加涉及9个大规模部署（〜60 m3）的自由浮动浮动层中的大规模的海洋水域的大型实验，这是德国资助的生物酸计划的一部分。 Bigelow新的中验设施进行的两个重复实验将进一步扩大DMS-OA研究的环境范围。通过标准分析方法的结合，最近开发的最先进的示踪剂方法来确定过程速率，以及与生物硫循环有关的微生物的潜在生物体多样性和遗传反应，他们将确定pH的变化如何影响关键的生物学途径，控制DMS的浓度以及在实验中负责的有机体。更广泛的影响：生成的信息将用于告知全球大气耦合模型的持续发展，能够检查海洋酸化对气候变化的影响。该信息还将用于进一步开发基于生理的机械方法来生物地球化学生态系统模型。博士后研究科学家将接受实验方法的培训，将通过与欧洲科学家合作来获得建模经验，并将开发国际和美国的合作，以增强我们对海洋对生态系统功能的酸化的理解。四名本科生，两个实习生和两个REU学生将通过参加Bigelow实验获得宝贵的经验。具有数学背景的额外的本科生将受到指导并参与解释和建模方面。作为既定的Bigelow计划的一部分，将向K-12学生和老师以及公众进行广泛的宣传，所有PI都将参加该计划（Bloom，Cafe Scientifique）。与科尔比学院（Colly College）（改变海洋学期）和岛屿研究所的联合计划将分别访问本科生和缅因州K-8学校。